Present-day production and packaging facilities increasingly require shorter cycle times while often having complex traverses. In order to put into effect these shorter cycle times, production and packaging facilities comprise at least one robot structure which may be moved around numerous axes, the robot structure moving an actuator arranged at the robot structure. At the same time, there is an endeavor in present-day production and packaging facilities to reduce cycle times with identical trayerse. In order to reduce the present cycle times, e.g. the moving masses of the used robots of production and packaging facilities may be reduced in order to be able to accelerate the robots' robot kinematics more quickly.
For assembling a light-built robot, the cable robot known from U.S. Pat. No. 4,666,362 is suitable. The moving masses of the cable robot are small in particular due to the fact that the drives for the individual various axes do not have to be moved together with the robot. Furthermore, cables of the cable robot may take up and transfer major loads while simultaneously having a low weight.
The cable robot known from U.S. Pat. No. 4,666,362 comprises a drive platform and a work plate which is spaced from the drive platform, the work plate being connected to the drive platform by means of a spacer rod. Furthermore, the work plate and the drive platform are coupled with six cable pulls, wherein the cable pulls are each actuated by one cable pull drive which is arranged at the drive platform and which variably alters the length of the corresponding cable pull. By specifically controlling the individual cable pull drives and thus the cable pulls, the work plate may be moved in six axial directions. One of these axial directions is a rotation of the work plate about its surface normal. However, the assembly of the robot known from U.S. Pat. No. 4,666,362 only allows for a very limited rotation angle.
Further, from U.S. Pat. No. 5,114,300 a robot structure comprising a first robot module having a first and a second platform is known. The first and the second platforms are connected via various elements which may be adjusted in their lengths. Furthermore, the second robot module is arranged at the second platform, the second robot module having the same structure as the first robot module. Due to the length-adjustable elements, the second platform may be moved in space, twisted and/or tilted with regard to the first platform. The second robot module may also carry out these kinds of motion with regard to the first robot module. Various embodiments of linear actuators such as a screw bar, a cable-operated bar or a hydraulic/pneumatic cylinder are suggested as length-adjustable elements.